1. Field of the Invention
The inventions disclosed and taught herein relate generally to centrifugal fans; and more specifically relate to centrifugal fans used in cooling and other applications where entrained water and/or dust may be undesirable.
2. Description of the Related Art
U.S. Pat. No. 3,796,511 discloses a “blower is comprised of a substantially cylindrical housing having end walls and an arcuate wall forming a substantially cylindrical chamber. A discharge opening is formed in the arctuate wall and an intake opening is formed in at least one of the end walls. A cylindrical fan rotor is rotatably mounted within the chamber for drawing air into the chamber through the intake opening and for propelling it around the interior of the chamber and outwardly through the discharge opening. There is a slot in the arcuate wall adjacent the discharge opening, and a skinning member protrudes radially inwardly adjacent the slot for directing a thin layer of air adjacent the arcuate wall of the chamber outwardly through the slot so as to remove dust particles adjacent the outer peripheral edge of the housing wall.”
U.S. Pat. No. 3,953,183 discloses “apparatus for separating particles from a gas flow is provided, comprising: is provided on the concave side of each crest, the serrations winning A plurality of corrugated separator plates arranged in spaced parallel relation to each other and defining wave-like flow channels between each other. The warped surfaces of the separator plates are generated in cross-section by at least three circular arcs connected continuously and with alternating directions of curvature. The radius of each of the three circular arcs is different, the radius of the arc representing the crest being the smallest. The arcs define at least one crest between two troughs, forming an intake section and an outlet-section, respectively of each separator plate. A first separating chamber is provided opening towards the gas flow on the convex side of the crest and is formed by a blade projecting from the downstream side of the crest toward its upstream side and running along the crest. A plurality of serrations running along underneath the crests arranged opposite to the separating chambers of the crest of the adjacent separator plate. The smaller radius of the second arc and the serrations together with the separating chamber provide a narrowing of the duct toward the crest to increase the speed of the fluid flow. A collision occurs between the main upstream gas flow and a continuous gas flow recoil from the first separating chamber, causing a stationary micro-turbulence in the vicinity of the serrations without a significant loss of energy and speed, whereby even the smallest particles are separated by the serrations. Two additional separating chambers of specific cross-sections are provided strategically on the downstream past the crest, each retaining material particles not caught previously.”
U.S. Pat. No. 4,348,057 discloses “a blower having an exhaust fan which draws air through its intake opening from the face of the coal. The blower is provided with a first stage of closely-arranged small-diametered cylindrical-shaped individual centrifuges between its intake opening and the exhaust fan in which the dust-laden air spins as air is drawn therethrough and concentrates the dust in an annular surrounding portion which is separately drawn from the centrifuges through a conduit also evacuated by the exhaust fan. This conduit contains a sharply-reversing bend which effectively separates and discharges the dust into a collection chamber, e.g. a removable bin. A grid disposed ahead of the first stage of individual centrifuges prevents large size particles from entering the centrifuges; and a second stage of closely-arranged, similarly-operating individual centrifuges located in the conduit closer to the exhaust fan remove “fines” which were not discharged to the collection chamber. The thus cleaned air exiting from the conduit is combined by the fan with the dust-freed air drawn from the core of the individual centrifuges and is discharged to the mine return area.”
U.S. Pat. No. 4,581,051 discloses “an apparatus for the separation of liquid drops or particulate solids from a gas stream comprising a plurality of parallel separator plates, a flow passage being formed between every two separator plates, each separator plate having at least one wave crest disposed approximately in its center and two wave troughs disposed at its edge on the inlet side and the outlet side, respectively, and forming an inlet section and an outlet section, respectively, as well as impingement-wall sections formed between the wave crest and the wave troughs, a main phase-separator chamber open in a direction counter to the direction of the gas flow being formed externally on the wave crest. In accordance with the invention, high separation efficiency with low pressure drop or low energy loss is obtained by providing an inlet nozzle formed in the inlet section, the gas stream being directable by means of the inlet nozzle onto the region on the inlet side of the opposite impingement-wall section.”
U.S. Pat. No. 4,588,351 discloses a “centrifugal-type air blower for a vehicle occupant compartment that operates in a housing and during a defrost mode to deliver heated air to defrost the vehicle's windshield is provided with an automatic bleed-off valve arrangement that automatically exhausts from the blower housing to outside the vehicle any airborne particles such as snow and water centrifugally discharged by the blower in the defrost mode when the outside air temperature falls below a predetermined sub-freezing water temperature.”
U.S. Pat. No. 5,000,769 discloses a “system for ventilating a rail traction motor and for dynamically purifying the ventilation air, the system comprising a centrifugal fan (1) having radial blades (2) surrounded by a circular housing (3) and delivering air to the motor, and dynamic filter means on the path of the air delivered by the fan. The system includes a plane sheet (4) pierced by peripheral through openings (5) forming a diffusing screen and dividing the inside volume of the circular housing into an upstream chamber (6) connected to the air inlet of the fan, and a downstream chamber (7) connected to its outlet leading to the motor, an exhaust outlet (8) for exhausting impure air, the exhaust outlet being in the form of a sector on the periphery of the upstream chamber, and a separator element (9) disposed facing the opening and forming an obstacle to deflect air streams close to the blades of the fan towards a take-up section close to the exhaust opening.”
U.S. Pat. No. 6,648,935 discloses a “two stage extracting blower that cleans liquid and solid contaminants from supply air, and provides high velocity air for cooling equipment, personnel and/or structures. In a first air cleaning stage, the blower uses air velocity and the centrifugal force of a rotating impeller to separate heavier contaminants entrained in a dirty air stream into a rear partitioned chamber of the blower housing. In a second air cleaning stage, the blower uses centrifugal forces imparted by the impeller on lighter contaminants to cause the contaminants to be collected in a skimmer provided in the partially cleansed air stream prior to release of the air stream from the blower.”
U.S. Pat. No. 7,771,501 discloses a “blower having oil-mist blower is disclosed. The blower is provided with tubing fitting on the wind suction opening connecting in series to an oil-collection box module. The position of the venting tube of the blower is connected to cyclone-separator. The oil-collection box module includes a box body, oil-collection seat body, filter and a cover plate. The cyclone-separator includes manifold tubing, filtering aid and a top cover. When the blower is in operation, the oil-collection box module sucks in oil-mist exhaust gas to proceed with first filtering of oil spot after that via the venting tubing into the cyclone-separator to proceed with a second filtering of oil spot.”
The inventions disclosed and taught herein are directed to an improved device, method, and system to separate liquid and particulate matter from an air stream of a centrifugal fan.